An Immunologic Reagent Resource Core will be established in support of the three research projects to provide critical reagents to track the changes in immune phenotype in response to vaccination and infection. Antibodies and tetramers are unique reagents and have been proven to be powerful tools to facilitate innovative research in many fields of biomedical science. We have been successful in our effort to create and characterize a panel of monoclonal antibodies and Ig related fusion proteins to soluble and cell surface proteins using a variety of techniques. Specifically, the Resource will produce monoclonal antibodies from hybridomas that are already available in the core or obtained from the ATCC or individual investigators. The antibodies will be conjugated to the appropriate fluorochromes as specified in the research projects. In addition, the antibody core will establish a quality control system for production and testing of specificity, quality, and concentration of reagents before providing them to the individual projects. In collaboration with Dr. Bill Kwok, the core will also generate a series of class I and Class II tetramers, which will be used to track antigen-specific T cell response following infection or vaccination. This large-scale, coordinated effort will result in high quality reagents for the projects at a substantially reduced overall cost.